Method of humidifying air



Sept. 13, 1932. E. s. BucK L METHOD 0F HUMIDIFYING AIR Original FiledFeb. 27. 1929 S-Sheets-Sheet 1 LVVENTOR:

BY W @M ATTOPA'EL Sept. 13, 1932. E 5, B 1,877,223

METHOD OF HUMIDIFYING' AIR Original Filed Feb. 27. 1929 '5 Sheets-Sheet2 A TTORVEY.

Sept. 13. 1932 .E. s. BUCK 1,877,223 I METHOD OF HUMIDIFYING AIR IOriginal Filed Feb. 27. 1929 3 Sheets-Sheet 3 1N1 "ENTOR: v

Patented Sept. 13, 1932,

V UNITED STATES PATENT OFFICE v EVERETT BUCK, OF CINCINNATI, OHIO,ASSIG-NOR, BY MESNE ASSIGNMENTS, TO-

THE EDWARDS MANUFACTURING COMPANY, OF CINCINNATI, OHIO, A CORPORA- TIONOF OHIO METHOD OF HUMIDIFY'ING AIR Original application illed February27, 1929, Serial No. 343,047. Divided and this application filed April30, 1930. Serial No. 448,615.

It is the object of my invention to humidify air by introducingthereinto condensation of as acids or alkalies, or physical. impurities,

have been removed or neutralized, as a humidifying agent for humidifyingthe air used for heating a room, chamber or other enclosure; and,further, to automatically control the amount of humidification in theheated air by the amount or intensity of the heat supplied inheating theair.

It has been the experience in heating plants employing heated air as aheating medium that it is advisable to supply the air with moisture, asotherwise the heated air proceeding from the heating plant is too dryfor human comfort or for other living creatures, as well as forarticles, such as furniture, in the enclosure for human habitation oruse. It has been usual heretofore to supply moisture by evaporation fromwater supplied entraneously of the heating plant, as

from ahydrant or other source of moisture. It has been the experience inheating by means of a combustible fuel, such as gas, or

- hydrocarbon fuel, that condensate forms in the flue vapors, and thatmoisture is precipitated from the flue vapors, which condensate orpreciptated moisture has heretofore been an objectionable feature insuch heating, it having been necessary heretofore to provide means fordisposing of the same as a waste product, as by piping the same to awaste system or sewer.

In my invention I gainfully use this condensate or precipitated moistureas a humidifying agent, transferring the same, as the same arises, tothe passage for the air being heated.

I further employ such condensate or precipitated moisture as aproportional humidifying agent in such passage for the air being heated,my invention providing for supplying such condensate or precipitatedmoisture in varying quantity varying according to the amount ofcombustion and the temperature of the air being heated, and consequentvariations in the amount of heat supplied; and, further, my inventionprovides a balanced humidification proportional to the amount ofcombustion and heat supplied.

In my invention I employ vapor in the passage or flue for the productsof. combustion used in heating the air, cause'condensa- I tion of suchvapor, preferably purify this condensation or neutralize the deleteriousor other acids or alkalies therein, and use the preferably purifiedcondensation for humidifying the air heated by said products ofcombustion.

In employing my invention, the amount of condensation is preferablyregulated by the amount or temperature of the products of combustionpassing through the combustion passage or flue, so that the amount ofcondensation in substantially proportional to the amount of heatsupplied for heating the air, and the amount of air heated or the degreeof temperature to which the air is heated is proti on, further, theamount of condensation ob- I tainedfrom the products of combustion andsupplied to the heating air is substantially proportional to the amountor heat of the products of combustion and the corresponding amount ordegree of temperature of the heating air.

Thus a small amount of condensation is supplied to the heating air whenonly a small amount of heat is being supplied, for instance in temperateweather, when a small amount of humidification in the heated air isrequired,

and a proportional larger amount of condensation is supplied to theheating air as the amount or heat of theheating air is increased, forinstance in colder weather, when a greater amount of humidification inthe heated air is required.

The invention will be further readily understood from the followingdescription and claims, and from the drawings which illustrate a furnacefor heating air employing my improved method, although the structure orarrangement of the furnace orheating plant is immaterial within thescope of my present invention. I make no claim herein to the means forproducing and utilizing the humidification herein shown and described,

- having shown, described and claimed the same in a copendingapplication for patent on improvements in means for humidifying air forheating and other purposes, Serial No. 343,047, filed February 27, 1929,of which this application is a division, and issued as Patent No.1,778,447, dated January 13, 1931, and to which reference is here made.

In the drawings:

Fig. 1 is a perspective view of an exempli fying heating plant, partlybroken away.*

Fig. 2 is a vertical longitudinal section of the same, taken in theplane of the line -2-2 of Fig. 3, and partly broken away. 7

Fig. 3 is a vertical cross-section of the same, taken in the plane ofthe line 33 of Fig. 2, and partly broken away.

Fig. 4 is a detail view of the purifying means, showing an axial sectionof the same; I

and,

Fig. 5 is'a sectional detail view showing the blower, taken on the line55 of Fig. 1.

The heating plant may be a furnace, combined boiler and'economizer, orotherdevice for heating air. The heating plant is exemplified as afurnace comprising a fire-box 11, in which the heat is generated, as forinstance by means of gas burners 12 of suitable construction attached toa'manifold 13, with which a feed-pipe 14 connects, a control valve 15being in the feed-pipe.

Passages 21 are shown rectangular in cross-section provided with upperwalls 22, lower walls 23, and side Walls 24, 25. These passages areopen-ended as shown at 26, 27. These passages are arranged one above theother in the heater, and are spaced apart by spaces 31, which formpassages .crossingly arranged with relation to the passages 21. Thepassages 31 are open-ended as shown at 32, 33, and have side walls 34.

Connecting passages 35, 36, formed by deflectors 37, 38, having closedends, connect neighboring passages 21, such neighborin passages beingone above the other at the respective ends of said passages.

There is an inlet-port 39 communicating with the upper passage 21. Thelower passage 21 connects with an extension passage 41, which extendsdownwardly at one side of the fire-box, crosswise under the fire-box,

and-upwardly at the other side of the fire-box and of saidcross-passages, and at its upper end has an outlet-port 42 whichconnects with a hood 43, which directs the heated air into a drum 44,from which suitable heating pipes, shown at 45, provided with usualdampers 46, direct the heated air to the desired points of use, as tothe various rooms in a dwelling or to other spaces to be heated. Thehood and parts thereabove may if desired be omitted.

Thev passages 21 extend throughout the major portion of the width of theheater and, with the connecting passages 35, 36, formed by thedeflectors, form a serpentine passage for the air to be heated. Thedirectionof movement of the air in said passage is indicated by thearrows a. The air is received through the inlet-port 39 and isexemplified as having a general downward course in said passage abovethe fire-box. It is forced around the bottom of the fire-box and thenascends in the ascending stretch or extension of the passage, and isreceived through the discharge-port 42 of said passage.

The air to be heated is preferably forced in a direction reverse to thedirection of natural flow of heated air, which would be upward in theserpentine passage. The air to be heated is forced downward, as by meansof a blower 51, which comprises an electric motor 52 and a fan 53 in anintake chamber 54, to which a pipe 55 may lead from a suitable source. Ahood 56 is located between the blower and the inlet-port 39, and directsthe air into the air passage of the heater.

The products of combustion are received through an opening 61 in therear wall of the fire-box or combustion chamber. The respective upperwalls and lower walls of the passages 21 above the fire-box formrespectively the lower wall and the upper wall of the passages 31,crossingly arranged with relation to the first-named passages. The endsof. neighboring passages 31 above one another are connected at therespective ends of said passages by means of connecting passages 62, 63,formed by deflectors 64, 65, having closed ends. The passage for theproducts of combustion is'provided with an out let port 66, connectingwith a hood 67, from which a smoke-stack or flue 68 extends. The lowerone ofsaid deflectors connects the lower passage 31 with the opening 61in the fire- A serpentine passage extending back and forth is thusprovided for the products-of combustion, the course of the products of acombustion being indicated-by the arrows b.

The products of combustion have a serpentine passage back and forthbetween the passages through which the air being heated moves back andforth in a serpentine path. The products of combustion areseparated fromthe heated airby a single thickness of sheet metal which forms adividing wall between the passages through which the products ofcombustion and the air respectively pass, providing for extremetransference of heat to said air.

The outer walls of the furnace may be provided with suitable insulationexemplified at 69.

In the present exemplification, the products of combustion are receivedthrough the cross-passages and connecting passages formed by thedeflectors, which cross-passages are exemplified as rectangular incrosssection and extend back and forth throughout substantially thehorizontal cross-sectional area of the heater, and having thecross-passages for the. air being heated, also exemplified asrectangular in cross-section, extending back and forth crossinglybetween the same, and extending substantially throughout the horizontalcross-sectional area of the heater.

Single walls of metal are thus provided by this construction between thepassages for the products of combustion and the passages for the airbeing heated, enabling substantially all of the heat in the products ofcombustion to be transferred to the air being heated.

The cool incoming feed-air for the fur? nace passes first through theupper cross- 80 passages 21, where it is acted on by the cooler'portions of the products of combustion passing through the uppercross-passages 31, and has heat transferred thereto through the walls ofsaid passages. The air being heated is acted on progressively by hotterportions of the products of combustion as it proceeds to the wall of thefire-box, where it is acted on by the hottest portions of the productsof combustion.

40 The products of combustion arising from the heating elementpassthrough the crosspassages 31, the hottest portions of the products ofcombustion crosslng through the lower ones of said cross-passages andtransferring heat to the heating air at the other sides of said walls ofsaid cross-passages, the products of combustion cooling as they passthrough the upper ones of said cross-passages 31 for utilizingsubstantially all of the heat therein for heat transference to the heating air. I

The products of combustion contain vapor which is caused to condensepreferably in the heater, for instance in the form of beads 71 ofcondensation forming on the bottom surface of the wall 23a separating anair passage from the flue gas passage. The latent heat resulting fromthis condensing is transferred to the alr in the air passage 21a byconvection, thus adding to the heat of this air, and providing aneconomical factor in creating this condensation. This condensation isafterwards transferred into the current of heating air, and the coolingeffect which this 65 condensation has upon the air is counteracted bythe. heating efiect due to the condensing, and at the same time moistureis made available for humidifying purposes.

The beads of condensation are led from the passage or flue for theproducts of combustion at a cooler portion or portions in said productsof combustion to a hotter portion or portions of the air being heated,the air being heated at said latter portion or portions again vaporizingthe condensation and receiving the condensation as a humidifying agent.

Beads 71a of condensation may also form at a portion of the passage orflue for the products of combustion more distant from the fire-box ifgreater heat is applied to said products of combustion, for instance, asexemplified by the beads 71a of condensation forming on the bottomsurface of the Wall 236 between a passage for the products of combustionand a passage for the air being heated. The latter beads have a coursesimilar to the beads 71 for providing humidifica-- the walls beingpreferably slanted or formed in such manner so that the condensationwill flow toward the depressions 72, 7 2a, respectively. A pipe 7 3connects with the depression 72a for feeding the condensation therein tothe depression 7 2. Either one or both of said collecting means forcondensation may be rovided.

here may be deleterious substances or chemicals passing with the waterof condensation into the depressions 72, 7 2a. In order to counteract ornullify such deleterious substances, chemicals or condition. thecondensation is preferably purified before admission into the heatingair passage. A suitable purifying means for purifying the condensationis provided. This is exemplified as a body 75, contained in a container76, into which the condensation is led, for instance, by a pipe 77, fromthe depression 72.

This container is preferably a glass jar through which the condition ofthe purifying agent of reagent and the condition of the water ofcondensationv may be viewed. It is preferably placed on the outside ofthe furnace, and is shown provided with a screw-cap 78, supported by thefurnace, into which the threaded neck 7930f the jar 76 is arranged to bescrewed.

The pipe 77 passes from the interior of the furnace wall through anopening 81 in the furnace Wall, to the outside of the furnace wall, andthence through an opening 82 in said cap, the pipe preferably passingdownwardly in adjacency to the bottom of the con tainer so as preferablyto cause flow of the condensation through the purifying agent.

A pipe 85 connects with the cap and passes through an opening 86 in thewall of the furnace and into one of the heating air passages, preferablythe lower heating air passage 210, where the pipe 85 hasa dischargemouth 8?. The cap 7 8 may be supported by said pipes.

The water of condensation will normally be at a level in the pipe 77,for instance, at the level indicated at 88, above the outletST of thepipe 85 in the heating air passage 21?). There is a continual flow bygravity from the pipe 77 through the container 76 and the pipe- 85 andthrough the outlet 87. The higher level 88 of the water of condensationin the pipe 77 is also caused by the pressure of the heating air in thepassage 216. There is continuous water seal or water trap formed by saidpipes and the container to prevent the passage of unpurified products ofcombustion into'the heating air channel.

The water of condensation formed in the flue or assage of the productsof combustion While t 1e furnace is operating is provided in suflicientquantity to maintain a trap or seal in advance of the pipe 85 and toinsure a continuous passage of the water of condensation into theheating air passage.

The amount of condensation formed in the flue or passage of the productsof combustion is dependent on and proportional to the amount of heatbeing supplied to orpassing through the furnace, and the amount ofhumidifying agent absorbed by the heating air for properly humidifyingthe same is also proportional to the amount of such air or the degree oftemperature thereof passing through the heater, so that the supply ofcondensation for the air being heated is automatically regulated by theamount of heat'applied in the furnace and the amount of air or thedegree of temperature of the air being heated which passes through thefurnace.

If the furnace is being operated for producing a comparatively low heat,for instance in warmer weather, there is less condensation formed andless humidity required in the air passage 21. When, however, the furnaceis speeded up or caused to produce greater heat, there will be a greateramount of condensation formed for automatically supplying the greateramount of humidity required for the greater amount of air or the highertemperature of the air passing through the air passage 21.- The properamount of moisture is thus maintained in the heated air for respirationpurposes and for producing an atmosphere in the heated room or apartmentmost conducive to healthful living conditions.

A suitable ourif in a ent or rea ent eX- 75 D h C! 7 emplified at 7 forneutralizing the sulphuric acid, may be instanced as barium hydroxide orlime-stone.

The container for a heating plant delivering approximately 700 cubicfeet of heated air per minute may be of 2 quart size and the lime-stonetherein be of a weight of approximately 3 pounds.

A charge of said lime-stone in the container will last approximately twoyears during continuous operation of the heater.

Other impurities may be contained in the condensation depending on thefuel em ployed, whic may be determined by chemical analysis,precipitation and flotation, and a purifying agent or reagent which willneutralize, nullify or arrest such impurities contained in thecondensation may be employed in the container 76, the purifying agentacting as a filter, both chemical and mechanical for such impurities.As, for example, the air for combustion might contain sulphur dust andsilica dust. The sulphur will be chemically neutralized by thelime-stone and the silica will settle out by gravity or be held byadhesion to the filtering agent.

Instancing the condensation formed, it may be stated that the combustionof one hundred feet of a retort coal gas forms approximately 7 .92pounds of water vapor, H 0, which is invisible until condensed. Thiscondensation takes place below 212 Fahrenheit,

at atmospheric pressure, and forms in the passages or flue in theproducts of combustion, as hereinbefore stated. The water vaper in theheated gasesresults from the combustion of the hydrogen in the gas, and,if the exact amount of air is added for perfect combustion, suchresultant flue gases will have a dew-point of approximately 136 1Fahrenheit. a

The condensing is enhanced by having cool feed-air coact with the coolerportions of the products of combustion, by feeding said heating air andthe products of combustion in opposite directions at opposite sides ofthe separating walls between the same.

Such condensing will occur on the cool metal surfaces, even though theflue gases may be generally above the dew-point, and

when it occurs, the latent heat of condensa- .evaporation occurs be usethe gases are above their. dew-point, and the heat transfer }30 Lamazein this case, followingas before the basic law of thermo-dynamics,results in the cooling of the flue gases. p

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is: Y

1. A method of humidifying air being heated which comprises heating theair by flue gases, simultaneously Condensing water vapor constituent ofsaid flue gases and simultaneously transferring the condensate tothe airbeing heated.

2.,A method of humidifying air being heated which comprises heating theair by flue gases, simultaneously condensing water vapor constituent ofsaid flue gases, purifying the condensate and simultaneouslytransferring the condensate to the air being heated.

3. A method of humidifying air being heated which comprises heating theair by flue gases, condensing water vapor constituent of said flue gasesand transferring the condensate to the air sobeing heated asa'continuous operation,

4. Amethod-of humidifying air beingheatheatedwhich comprises subjectingthe prodf nets of combustion to the cooling action of air being heatedand caused to travel in a general direction reverse to the direction oftravel of the products of combustion for condensing flue va or in acooler portion of the products of combustion, and introducing thecondensation into a hotter portion of said air being heated incontinuous sequence.

9. A method of humidifying air being heated which comprises subjectingthe prodnets of combustion to the cooling action of air being heated andcaused to travel in a general direction reverse to the direction oftravel of.

the products of combustion for condensing flue vapor, purifying thecondensate, and introducing the condensate into said air being so heatedin continuous sequence.

In testimony whereof, I have hereunto signed my name.

- EVERETT S. BUCK.

said combustion, in continuous sequence and in volume proportional tothe heat of the combustion of the heating agency in heating the jss air.I

6. A method of humidifying air being heated for respiration or airconditioning puroses, which comprises condensing flue vapor mm theproducts of combustion heating the air while so heating the air,purifying said condensation, and transferring the purified Icondensation of flue vapor into the air while the air is being so heatedby the heat of said combustion, in continuous sequence and in volumeproportional to the heat of the combustion of the heating agency' inheating the air, and neutralizing said condensation during suchtransfer.

7. A method of humidifying' air being heated which comprises subjectingthe products of combustion to the cooling action of, air being heatedand caused to travel in a general direction reverse to the direction oftravel of the products of combustion for condensing flue vapor, andintroducing the condensation into said air being. heated in continuoussequence.

8. A method of. humidifying air being

